The invention relates to a wood chip or other material stacker used to form large piles of wood chips and other particulate or granular material. The invention particularly relates to supports for trusses in chip stacking devices.
Wood process plants, e.g., mills, convert logs into wood chips. The wood chips are stored in large piles. From these piles the wood chips are transported to, for example, a digester or refiner that converts the chips to pulp. The storage of wood chips in a pile is generally referred to as stacking the chips.
Conventional chip stacking devices (stackers) deliver the wood chips or other material to the piles and form the piles. Chip stackers typically are large structures, e.g., one-hundred (100) feet high, e.g., thirty three meters, and well over a hundred feet in length. Chips are delivered to an upper truss of the stacker. A conveyor in the truss transports the chips to the end of the truss where the chips are discharged and fall to the stack. The truss is a cantilever beam and extends from a support pillar high over the chip pile. The truss may pivot around the pillar to form a circular or arched shaped chip pile.
The cantilevered truss of a conventional chip stacking device is under tremendous stress due to force moments at the junctions of the truss and pillar and at the base of the pillar. These forces limit the length of the truss and thereby limit the size of the chip pile that can be formed by the chip stacking device. There is a long felt need for a chip stacker capable of forming larger chip piles than can be accommodated by cantilevered truss chip stackers.